METHOD FOR PERFORMING SOLID-LIQUID-GAS PHASE EQUILIBRIUM MEASUREMENTS OF SOLVENT + SOLUTE BINARY SYSTEMS.

摘要

The present invention aims to provide a novel method particularly useful in determining the solid-liquid-gas phase equilibrium of a binary system consisting of a solvent + solute. The solvent may be any compound considered a supercritical fluid, and the solute may be an organic solid phase compound under normal conditions. The basic measurement principle is a basis for the pressure change detection as criteria for considering the solid-liquid-gas balance of the binary system in a constant volume device. The process consists of starting from fluid phases and decreasing the necessary temperature slowly for the pressure consequently also drops. The formation of the solid phase (solid-liquid-gas balance criteria) establishes when the pressure increases at the same time that the temperature continues to decrease. According to the results obtained, the present invention exhibits being highly reliable according to the repeatability analyze of each experimental point determined in this work. The measurement range is performed from up to 0.1 MPa, at pressures of up to 45 MPa or in the region close to the upper terminal critical point (UCEP).